Search results for "Parasitism"

Constraining the Deep Origin of Parasitic Flatworms and Host-Interactions with Fossil Evidence

2015

Novel fossil discoveries have contributed to our understanding of the evolutionary appearance of parasitism in flatworms. Furthermore, genetic analyses with greater coverage have shifted our views on the coevolution of parasitic flatworms and their hosts. The putative record of parasitic flatworms is consistent with extant host associations and so can be used to put constraints on the evolutionary origin of the parasites themselves. The future lies in new molecular clock analyses combined with additional discoveries of exceptionally preserved flatworms associated with hosts and coprolites. Besides direct evidence, the host fossil record and biogeography have the potential to constrain their…

BLOOD PARASITES AND MALE FITNESS IN THE PIED FLYCATCHER

1993

In vertebrates the effect of parasites on host ecology has almost been ignored. Recently the view that well-adapted parasites do not harm their hosts has been challenged and there is growing evidence that parasites do have a present-day effect on a great variety of host fitness components. The pied flycatcher is a small migratory passcrine bird. Any decrease in condition caused by disease should affect its ability to cope with physical demands of migration. Here we examine whether blood parasites have any effect on male arrival time. Males infected with Trypanosoma arrived on average 2 days later than males with no Trypanosoma infection. Infected males also had shorted tails and tended to h…

Interspecific extrinsic and intrinsic competitive interactions in egg parasitoids

2012

Interspecific competitive interactions can occur either between adult parasitoids searching/exploiting hosts (extrinsic competition) or between parasitoid larvae developing within the same host (intrinsic competition). Understanding how interspecific competition between parasitoids can affect pest suppression is important for improving biological pest control. The purpose of this work was to review both extrinsic and intrinsic competition between egg parasitoid species. These are organisms that are often candidates for biological control programs due to their ability to kill the pest before the crop feeding stage. We first reviewed the literature about interspecific competitive abilities of…

A New Species ofTelenomusHaliday (Hymenoptera: Scelionidae) Associated with Egg Batches of the Pine Processionary Moth,Thaumetopoea pityocampa(Dennis…

2009

Telenomus thaumetopoeae Buhl sp. n. is described from northeastern València (Peninsular Spain) taking as starting point females parasitizing the egg-batches of the Pine Processionary Moth, Thaumetopoea pityocampa (Dennis et Schiffermüller, 1775). Its morphological affinities with the most closely related species and parasitism data are offered.

First helminthological data on Iberian vipers: Helminth communities and host-parasite relationships

2006

AbstractEuropean vipers are ambush predators with sporadic feeding events, thereby maintaining the digestive tract empty for long periods. According to previous studies relating lizards’ dietary habits and their helminth faunas, we predict poor gastrointestinal helminth communities in vipers. To test this hypothesis, we have examined the digestive tract of 86 specimens of Vipera aspis (L., 1758) and V. latastei Boscá, 1878, from several localities of the Iberian Peninsula. We found adults of only two nematode species Kalicephalus viperae (Rud., 1819) and Ophidascaris sp. and cysts adhering to the external wall on the stomach in case of two other nematode species Ascarops strongylina (Rud., …

Dazzled and confused? Habituation and sensitization in free-living Yellow Warblers

2004

Cowbird versus cuckoo hosts: a comparative study of learned nest defense

2005

One of the best example of coevolutionaru adaptations is that of the interactions between avian brood parasites and their hosts. Brood parasites lay their eggs in nests of other specieis and leave the job of caring for their young with the hosts. Hosts of brood parasites tend to suffer high reproductive costs as often they raise few of no young of their own, an effect of being parasitizes. For this reason, many hosts have evolved strategies that reduces the cost of parasitism.

Social transmission in avian brood parasitism systems

Obligate brood parasites lay all of their eggs in nests of other species, leaving the burden of parental care entirely to the hosts. As a consequence of being parasitized, hosts’ reproductive success is often reduced. This strategy has triggered a coevolutionary dynamic involving behavioural, physiological and morphological adaptations and counter-adaptations from the two players, whose conflicting functions are to successfully parasitize a nest, and prevent or reduce the negative effects of parasitism. In parasite systems studied in the New and Old worlds, warbler hosts exhibited different degrees of learning antiparasite defences from conspecifics. By quantifying strength and direction of…

Digeneans of cetaceans: taxonomy, evolutionary history and host specificity.

2016

Parasitism is an extremely successful lifestyle among animals. In fact, every free-living organism is believed to harbour at least a parasite species, and cetaceans are not the exception. Host-parasite systems offer a suitable model for studying systematics, evolution, biogeography and ecology because the evolutionary fate of parasites is linked to that of their hosts. In particular, present-day associations between cetaceans and their parasites have been shaped by unique historical events. The parasites of the terrestrial ancestors of cetaceans likely faced an ecological barrier when their hosts colonized the marine environment; it is postulated that during the process terrestrial parasite…

Microorganisms and Biotic Interactions

2014

SPE IPM; Most ecosystems are populated by a large number of diversified microorganisms, which interact with one another and form complex interaction networks. In addition, some of these microorganisms may colonize the surface or internal parts of plants and animals, thereby providing an additional level of interaction complexity. These microbial relations range from intraspecific to interspecific interactions, and from simple short-term interactions to intricate long-term ones. They have played a key role in the formation of plant and animal kingdoms, often resulting in coevolution; they control the size, activity level, and diversity patterns of microbial communities. Therefore, they modul…